CN114469293A

CN114469293A - External bone fixation system

Info

Publication number: CN114469293A
Application number: CN202111652655.3A
Authority: CN
Inventors: 迈克尔·马拉尼
Original assignee: Amdt Holdings Inc
Current assignee: Amdt Holdings Inc
Priority date: 2016-07-14
Filing date: 2017-02-10
Publication date: 2022-05-13
Also published as: JP2024028709A; CN109069187B; US20180344354A1; AU2021286343B2; EP3426172C0; JP6966460B2; EP3426172A1; EP3426172B1; AU2017217654A1; BR112018016282A2; US10856908B2; WO2017139517A1; US11969191B2; CA3014098A1; EP4233748A3; AU2020200044A1; JP7390347B2; EP4233748A2; AU2020200044B2; AU2017217654B2

Abstract

The present application provides an extraosseous fixation system. The system includes one or more pairs of bone fixation platforms in the form of rings or partial rings. The platform may be coupled to a respective bone segment. The pair of platforms is adapted to receive a plurality of stanchions extending between the platforms. The strut is for coupling to the platform by a joint that can provide three degrees of freedom of rotation. The struts also serve to enable the longitudinal length of the strut extending between the joints or platforms to be incrementally adjusted as the strut is attached to the platform. The strut also serves to enable the overall length adjustment range of the strut to be increased by coupling at least one additional component to the strut in situ. Each strut of the plurality of struts is adjustable in length, particularly in relative position and orientation, for deploying the platform to deploy a bone segment coupled to the platform.

Description

External bone fixation system

Reference to related applications

The application is a divisional application of Chinese patent application with the application date of 2017, 2, 10 and the application number of 201780022570.2 and named as an 'external bone fixation system'.

Technical Field

The present invention relates generally to external bone fixation systems (external bone fixation systems) and related methods. More particularly, the present invention relates to an extraosseous fixation system comprising a plurality of length adjustable struts (strut) rotatably coupled between a pair of platforms for fixation of bone segments and related methods.

Background

External fixation devices have been used to: bone and tissue conditions are treated by positioning bone or tissue segments in desired relative positions based on specific clinical needs. One form of external fixation device is a hexapod fixation device. A hexapod fixture (otherwise known as a Stewart platform) includes a six degree of freedom (6DOF) parallel controller or strut. Generally, these devices are capable of controlling translation of the target object relative to the base in all three orthogonal axes (X, Y, Z positions) and all rotation (pitch, roll, yaw) about these three orthogonal axes.

When used as a bone or tissue fixation system, a hexapod system typically includes a pair of rings that serve as bone fixation platforms. The platforms are typically coupled with six struts extending between the platforms. The mast and the platform are usually coupled by a ball joint or a universal joint, enabling rotation about three orthogonal axes respectively. While some of these struts are capable of length adjustment, the minimum and/or maximum lengths of these struts may not meet the needs of a particular clinical situation. For example, if the distance between the platforms is minimized to less than that provided by a particular strut, then shorter struts would need to be used, which naturally limits the range of adjustability (i.e., maximum length) of the struts.

Thus, existing hexapod bone fixation systems utilize a set of struts of different lengths (or a range of different lengths), providing "short" struts when the platforms need to be close together and "long" struts for use when the platforms need to be separated. In many cases, these struts must be replaced with struts of another length, step-by-step or step-by-step, during the bone or tissue correction process, which is a time consuming and costly process because the replaced struts cannot be reused. In addition, some situations require a variety of different strut lengths, which complicates such systems. For example, when there are extreme initial angles or rotations, various strut lengths are often required. In this case, the selection process of the correct combination of different strut lengths is usually achieved by trial and error in the operating room, which is very time consuming. Such systems and situations also require a large inventory, are costly, and often are not clear how to utilize properly.

In addition, physically changing the struts also limits the usable dynamic range of the system when attempting to reduce deformities in a dramatic manner. In this case, the struts are not typically added until after such acute correction is completed, and are reduced by the operating room staff and selected by other members than the operating room staff between the designated locations as to which struts are suitable between the platforms. This process is time consuming and requires a large inventory.

Current hexapod fixation systems also typically utilize connections between the platform and the strut that require the use of one or more fasteners to fasten when applied. As such, sometimes connecting six struts at both ends to a platform in a trial-and-error manner (i.e., twelve connections) is a difficult and time-consuming task. Many existing hexapod fixation systems use loose fasteners, which complicates the problem because these fasteners require the use of instrumentation to apply them. These fasteners and instruments add to the collection process of components and materials for tracking in the operating room when using the fixation system (e.g., when attempting to maintain a reduction).

Accordingly, there is a need for a hexapod fixation system and associated method that provides an increased range of length adjustment while remaining coupled to the platform, reduces the amount of associated inventory, can be installed relatively quickly, and reduces costs.

Disclosure of Invention

In one aspect, the present invention provides an extraosseous fixation system comprising a first platform, a second platform and at least six length adjustable strut assemblies. The first platform defines an opening and is for coupling to a first bone segment. The second platform defines an opening and is for coupling to a second bone segment. Each strut assembly includes an externally threaded rod portion translatable through a strut body portion. The stem portion of each strut assembly is coupled to one of the first and second platforms by a respective joint, and the strut portion of each strut assembly is coupled to the other of the first and second platforms by a respective joint. The strut assemblies are coupled to the first and second platforms in pairs of strut assemblies spaced about the first and second platforms. The pair of strut assemblies each include a first strut assembly coupled to the respective platform by a joint of the threaded rod portion of the first strut assembly and a second strut assembly coupled to the respective platform by a joint of the strut body portion of the second strut assembly.

In another aspect, the present invention provides an extraosseous fixation system comprising a first platform, a second platform and a plurality of length adjustable strut assemblies. The first platform is for coupling to a first bone segment and defines an opening. The second platform is for coupling to a second bone segment and defines an opening. The strut assembly extends between the first platform and the second platform within an operable range of angles or directions relative to the platforms. At least one of the stem portion and the body portion of each strut assembly is attached to one of the first platform and the second platform by: engaging the respective platform with the strut assembly at an inoperable angle or orientation and rotating the strut assembly to an operable angle or orientation range.

In yet another aspect, the present invention provides a strut assembly for an extraosseous fixation system. The strut assembly includes a strut body portion, an externally threaded first rod portion, and an externally threaded additional rod portion. The abutment body portion includes a cavity extending therethrough and internal threads. The abutment body portion further comprises a first joint at one end of the abutment body portion for coupling to a fixed platform. The first stem portion is translatable through the abutment body portion. The first pole section includes a second knuckle at one end of the first pole section for coupling to a fixed platform. An externally threaded additional rod portion is for attachment to the first rod portion to extend the length of the first rod portion. The length between the first joint and the second joint can be adjusted. The additional rod portion is attachable to the first rod portion when the first joint and the second joint are each coupled to the platform.

These and other objects, features and advantages of the present invention will become apparent from the following detailed description of the various aspects of the invention, which is to be read in connection with the accompanying drawings.

Drawings

For purposes of illustrating the extraosseous fixation systems and related methods described herein, illustrative embodiments are shown. These illustrative embodiments do not limit the precise arrangement and operation of the disclosed external fixation system, and other similar embodiments may be devised based thereon.

Fig. 1 is a perspective view of an extraosseous fixation system in a first configuration corresponding to the most compact configuration comprising a plurality of platforms and a plurality of interconnected strut assemblies.

Fig. 2 is a perspective view of the extraosseous fixation system of fig. 1 in a second configuration corresponding to an expanded configuration or state.

Fig. 3 is a perspective view of the strut assembly of the extraosseous fixation system of fig. 1 shown in its most compact state.

Fig. 4 is a side view of the strut assembly of the extraosseous fixation system of fig. 1 shown in an extended configuration or state.

Fig. 5 is a front view of the strut assembly of fig. 4.

Figure 6 is a side cross-sectional view of the strut assembly of figure 4 as shown in figure 5.

Fig. 7 is a front cross-sectional view of the strut assembly of fig. 4 as shown in fig. 4.

Figure 8 is a cross-sectional view of the strut assembly of figure 4 as shown in figure 4.

Figure 9 is a cross-sectional view of the strut assembly of figure 4 as shown in figure 4.

Figure 10 is a cross-sectional view of the strut assembly of figure 4 as shown in figure 5.

Fig. 11 is an exploded view of a release mechanism of a strut assembly of the extraosseous fixation system of fig. 1.

FIG. 12 is an exploded view of the pre-installed rod portion, connecting element, and additional rod portion.

Fig. 13 to 17 show the connecting element of fig. 12 progressively connecting the pre-mounted rod portion and the additional rod portion.

FIG. 18 is a detailed view of the mating geometry of the pre-installed rod portion and the additional rod portion of FIG. 12.

Fig. 19 is an exploded view of a joint mechanism of a strut assembly of the extraosseous fixation system of fig. 1.

Fig. 20 illustrates a perspective view of a platform of a strut assembly of the extraosseous fixation system of fig. 1.

FIG. 21 is a perspective view of the strut assembly aligned with the strut of the platform in an inoperable orientation.

FIG. 22 is a perspective view of the strut assembly of FIG. 21 engaged with a strut of a platform in an inoperable orientation.

FIG. 23 is a perspective view of a strut assembly coupled to a strut of the platform of FIG. 21 by rotating the strut into an operable orientation.

Fig. 24 is an exploded view of the joint mechanism of the threaded rod portion of the strut assembly of the extraosseous fixation system of fig. 1.

Fig. 25 is a perspective view of an exemplary interconnected strut assembly of another exemplary extrabony fixation system according to the present invention in a first configuration.

FIG. 26 is a side view of the interconnected strut assembly of FIG. 25.

FIG. 27 is a top view of the interconnected strut assembly of FIG. 25.

FIG. 28 is a perspective view of the interconnected strut assembly of FIG. 25 in a second configuration.

FIG. 29 is a top view of the interconnected strut assembly of FIG. 25 in a second configuration.

FIG. 30 is a side view of the interconnected strut assembly of FIG. 25 in a second configuration.

Fig. 31 is a perspective view of the interconnected strut assembly of fig. 25 in a collapsed third configuration and coupled with a platform of an extraosseous fixation system.

Fig. 32 is a top view of the extraosseous fixation system of fig. 31.

Fig. 33 is a side view of the extraosseous fixation system of fig. 31.

Fig. 34 is a bottom perspective view of the extraosseous fixation system of fig. 31 with the interconnected strut assembly in an extended configuration.

Fig. 35 is a front perspective view of the extraosseous fixation system of fig. 33.

Fig. 36 is a side view of the extraosseous fixation system of fig. 33.

Figure 37 is a perspective view of the interconnected strut assembly of figure 25 in a third configuration and a platform of an extraosseous fixation system.

Fig. 38 is a perspective view of the interconnected strut assembly of fig. 25 in an extended configuration and a platform of an extraosseous fixation system.

Fig. 39 is a perspective view of the interconnected strut assembly of fig. 25 in an extended configuration and the platform of the connected extraosseous fixation system.

Figure 40 illustrates a bottom perspective view and a side view of the interconnected strut assembly of figure 25 in a collapsed third configuration and the platform of the connected extraosseous fixation system.

Figure 41 illustrates a bottom perspective view and a side view of the interconnected strut assembly of figure 25 in a collapsed third configuration with the accessory bar installed and the platform of the connected extraosseous fixation system.

Fig. 42 is a top perspective view of a strut-platform connection mechanism coupling a pair of strut assemblies of the extraosseous fixation system of fig. 25.

Fig. 43 is a bottom perspective view of the strut-platform connection mechanism of fig. 42.

FIG. 44 is a top perspective view of the strut-platform connection mechanism of FIG. 42 coupling a pair of strut assemblies to a platform.

FIG. 45 is a bottom perspective view of the strut-platform connection mechanism of FIG. 42 coupling a pair of strut assemblies to a platform.

Fig. 46 is a top view of the platform of the extraosseous fixation system of fig. 25.

Fig. 47 is an exploded perspective view of an exemplary strut assembly of the extraosseous fixation system of fig. 25.

Fig. 48 is an exploded perspective view of an exemplary length adjustment mechanism of a strut assembly of the extraosseous fixation system of fig. 25.

Fig. 49 is an exploded perspective view of an exemplary length adjustment mechanism of a strut assembly of the extraosseous fixation system of fig. 25.

FIG. 50 is a perspective view of an exemplary partially threaded nut of the length adjustment mechanism of FIG. 48.

Fig. 51 is a side view of the partially threaded nut of fig. 50.

Fig. 52 is a cross-sectional view of the partially threaded nut of fig. 50.

Fig. 53 is a perspective view of the example length adjustment mechanism of fig. 48.

FIG. 54 is a side cross-sectional view of the example length adjustment mechanism of FIG. 48 in an activated state.

FIG. 55 is a side cross-sectional view of the example length adjustment mechanism of FIG. 48 in a deactivated state.

FIG. 56 is a cross-sectional view of the example length adjustment mechanism of FIG. 48 in an activated state.

FIG. 57 is a cross-sectional view of the example length adjustment mechanism of FIG. 48 in a deactivated state.

Fig. 58 is an exploded perspective view of the example length adjustment mechanism of fig. 48.

Fig. 59 is a perspective view of an exemplary interconnected strut assembly of another exemplary extraosseous fixation system according to the present invention.

FIG. 60 is a top view of the interconnected strut assembly of FIG. 59.

FIG. 61 is a front perspective view of the interconnected strut assembly of FIG. 59.

FIG. 62 is a bottom perspective view of the interconnected strut assembly of FIG. 59.

FIG. 63 is a front perspective view of the interconnected strut assembly of FIG. 59.

Fig. 64 is a side view of the extraosseous fixation system of fig. 59 with the interconnected strut assemblies coupled to the plurality of platforms.

Fig. 65 is an elevational perspective view of the extraosseous fixation system of fig. 59 showing bone segments.

Fig. 66 is an elevational perspective view of the extraosseous fixation system of fig. 59 showing the attachment mechanism attaching a pair of strut assemblies to the platform.

Fig. 67 is a bottom perspective view of the extraosseous fixation system of fig. 59 showing the connection mechanism connecting the pair of strut assemblies to the platform.

Fig. 68 is an elevational perspective view of the extraosseous fixation system of fig. 59 showing the attachment mechanism attaching a pair of strut assemblies to a pair of platforms.

Fig. 69 is a perspective view of the extraosseous fixation system of fig. 59 showing the strut-platform connection mechanism.

Fig. 70 is a side view of the extraosseous fixation system of fig. 59 showing the strut-platform connection mechanism.

Fig. 71 is a perspective view of an exemplary length adjustment mechanism of a strut assembly of the extraosseous fixation system of fig. 59.

Fig. 72 is a side view of the length adjustment mechanism of fig. 71.

Fig. 73 is a cross-sectional view of the length adjustment mechanism of fig. 71.

FIG. 74 is another cross-sectional view of the length adjustment mechanism of FIG. 71.

FIG. 75 is another cross-sectional view of the length adjustment mechanism of FIG. 71.

FIG. 76 is another cross-sectional view of the length adjustment mechanism of FIG. 71.

Fig. 77 is an exploded perspective view of the length adjustment mechanism of fig. 71.

FIG. 78 is another exploded perspective view of the length adjustment mechanism of FIG. 71.

Fig. 79 is a side exploded view of the length adjustment mechanism of fig. 71.

FIG. 80 is another side exploded view of the length adjustment mechanism of FIG. 71.

FIG. 81 is another cross-sectional view of the length adjustment mechanism of FIG. 71.

Fig. 82 is a perspective view of another exemplary external bone fixation system in accordance with the present invention.

Fig. 83 is an external elevational perspective view of the strut-platform connection mechanism of the extraosseous fixation system of fig. 82 connecting a pair of strut assemblies to a platform.

FIG. 84 is an outer bottom perspective view of the strut-platform connection mechanism of FIG. 83.

FIG. 85 is an interior front perspective view of the strut-platform connection mechanism of FIG. 83.

Fig. 86 is a top view of the platform of the extraosseous fixation system of fig. 82.

Fig. 87 is a front perspective view of the platform of fig. 86.

Fig. 88 is an enlarged front perspective view of the platform of fig. 86.

Fig. 89 is a side perspective view of the platform of fig. 86.

Fig. 90 is an outer bottom perspective view of the strut-platform connection mechanism of fig. 83 connected to the platform of fig. 86.

Fig. 91 is a top view of the strut-platform connection mechanism of fig. 90.

Fig. 92 is a side view of the strut-platform connection mechanism of fig. 90.

Fig. 93 is a cross-sectional view of the strut-platform connection mechanism of fig. 90.

Fig. 94 is a perspective view of the strut-platform connection mechanism of fig. 83.

Fig. 95 is a side view of the strut-platform connection mechanism of fig. 94.

Fig. 96 is a top view of the strut-platform connection mechanism of fig. 94.

Fig. 97 is a cross-sectional view of the strut-platform connection mechanism of fig. 94.

Fig. 98 is another cross-sectional view of the strut-platform connection mechanism of fig. 94.

Fig. 99 is a perspective view of the linkage mount of the strut-platform linkage of fig. 83.

Fig. 100 is a front view of the attachment mechanism mount of fig. 99.

Fig. 101 is a side view of the attachment mechanism mount of fig. 99.

Fig. 102 is a cross-sectional view of the attachment mechanism mounting bracket of fig. 99.

Fig. 103 is a top view of the attachment mechanism mount of fig. 99.

Fig. 104 is another cross-sectional view of the attachment mechanism mounting bracket of fig. 99.

Fig. 105 is another cross-sectional view of the attachment mechanism mounting bracket of fig. 99.

Detailed Description

When introducing elements of various embodiments of the present invention, the articles "a," "an," "the," and "said" are intended to mean that there are one or more of the elements. The terms "comprising," "including," and "having" are intended to be inclusive and mean that there may be additional elements other than the listed elements. Any examples of parameters do not exclude other parameters of the disclosed embodiments. The components, aspects, features, configurations, arrangements, uses, etc. described, illustrated, or otherwise disclosed herein with respect to any particular embodiment may be similarly applied to any other embodiment disclosed herein.

The present invention provides a six degree of freedom (6DOF) bone or tissue fixation system and associated fixation method 100 as shown in fig. 1-18, the system and method 100 having the desired stability and mobility characteristics of a hexapod system, overcoming time consuming strut length selection and assembly difficulties. As shown in fig. 1-18, the fixation system 100 also includes a strut assembly 110 having a greater dynamic range so that the drastic reduction that occurs in the operating room is not limited by the system 100 itself and one or more struts 110 need not be selected and replaced during the reduction. In some embodiments, the fixation systems and associated fixation methods 100 of the present invention, as shown in fig. 1-18, are particularly advantageous for repairing fractures or deformities, such as fractures or deformities of longer bones.

In one embodiment, the fixation system or device 100 includes strut assemblies, each formed from a threaded rod assembly 25, the threaded rod assembly 25 being threadably coupled within the strut 5. As further explained below, the threaded rod assembly 25 may include a first strut screw or threaded rod 12, and may also include a second additional strut screw or threaded rod 13. As shown in fig. 1-7, 10, 12 and 13, the threaded rod assembly 25 may include external threads. As shown in fig. 1-3, the threaded rod assembly 25 may include or define a longitudinal axis X-X and may be elongated along the axis X-X. In some embodiments, the threaded rod assembly 25 may be cylindrical. As shown in fig. 3, the threaded rod assembly 25 (which includes external threads) may define a length L1 along the longitudinal axis X-X.

As shown in fig. 1 to 7 and 11, the threaded rod assembly 25 may be translatably housed within the abutment body 5. Thus, the abutment 5 may comprise an unthreaded and possibly substantially smooth cavity for receiving the abutment 5 therein or for receiving the abutment 5 therethrough (e.g. along the longitudinal axis X-X). The abutment 5 and its possible cavity may define a length L2 along the longitudinal axis X-X, as shown in fig. 3, which length L2 is less than the length L1 of the threaded rod assembly 25. As shown in fig. 1, 3-7, 16, and 17, the abutment 5 may be used to allow the abutment 5 to freely extend and/or translate through the abutment 5. As explained further below, one end of the strut 5 may be coupled to the first platform 120 and the other end of the threaded rod assembly 25 may be coupled to the second platform 130. In this manner, the abutment body 5 and the threaded rod assembly 25 may be translated relative to each other along the axis X-X to provide a relatively wide range of length adjustability for the abutment assembly 110 such that the distance and/or direction between the first platform 120 and the second platform 130 is as shown in fig. 1 and 2.

As explained further below, the first platform 120 and the second platform 130 may be rings or partial rings such that they extend at least partially around the opening and/or axis X2-X2 (and possibly extend at least partially around bone and/or tissue in situ). Strut assembly 110 may be coupled to first platform 120 and second platform 130 about axis X2-X2. For example, as shown in fig. 1 and 2, strut assemblies 110 may be circumferentially positioned and coupled to first and second platforms 120,130, and each strut assembly 110 may be attached to first and second platforms 120,130 at different locations about axis X2-X2. As such, strut assembly 110 may be angled relative to axis X2-X2.

As shown in fig. 1 and 2, the strut assembly 110 may be arranged to couple with the first platform 120 and the second platform 130 in the following configuration: providing clearance for the threaded rod assembly 25 to extend from the abutment 5 (and vice versa). For example, strut assemblies 110 may be coupled to first platform 120 and second platform 130 in pairs of adjacent and relatively dense joints, and such pairs of strut assemblies 110 may be spaced relatively closer together around first platform 120 and second platform 130 (and thus around axis X2-X2). Each pair of strut assemblies 110 may include a joint coupling the threaded rod assembly 25 of one strut assembly 110 to the first platform 120 or the second platform 130, and a joint coupling the strut 5 of the other strut assembly 110 to the first platform 120 or the second platform 130. Thus, the strut assemblies 110 are engaged to the first platform 120 and the second platform 130 in an alternating pattern or orientation.

Each pair of strut assemblies 110 coupled with the first platform 120 and the second platform 130 may extend in opposite angular directions about the axis X2-X2 to the other platform 120,130, where one strut assembly 110 may extend and be coupled to the other platform 120,130 at a different clockwise position and the other strut assembly 110 may extend and be coupled to the other platform 120,130 at a different counterclockwise position.

As described above, the strut assembly 110 may be used to enable the threaded rod assembly 25 to extend completely through the strut body 5, for example as shown in the dispersed arrangement shown in fig. 1 and 3. Since each pair of strut assemblies 110 includes one joint coupling the threaded rod assembly 25 of the first strut assembly 110 to the respective first platform 120 or second platform 130, and one joint coupling the strut 5 connecting the second strut assembly 110 to the respective first platform 120 or second platform 130; as shown in fig. 1, the threaded rod assembly 25 of the second mast assembly 110 is able to extend from the mast 5 (coupled with the respective first platform 120 or second platform 130) without interference from the first mast assembly 110. Thus, the alternating orientation of strut assemblies 110 in the pair of strut assemblies 110 coupled with first platform 120 and second platform 130 enables threaded rod assembly 25 to define a relatively long length L1. In this manner, as shown in fig. 1, the system 100 can be used to drastically reduce the distance between the first platform 120 and the second platform 130 (and the bone or tissue segments to which the first platform 120 and the second platform 130 are connected) while still being used to adjust to the relatively large distance (i.e., relatively large separation) shown in fig. 2. Thereby providing a relatively large dynamic envelope of adjustability of first and second platforms 120,130 without the need to replace or add to strut assembly 110, which may facilitate a surgeon focusing on orthopaedic conditions and reducing fractures or deformities.

As shown in fig. 3-7 and as described above, a threaded rod assembly 25 (i.e., a first strut screw or threaded rod 12, and possibly a second additional strut screw or threaded rod 13) may be disposed within the open mouth of the strut body 5 and threadably engage corresponding internal threads of the strut body 5. Whereby the strut assembly 110 (via the threaded rod assembly 25 and the strut 5) is removed from the prismatic joint. In some embodiments, as shown in fig. 6, 7, 10, and 11, the post 5 of the post assembly 110 may be threadably engaged with the threaded rod assembly 25 by at least one thread (key) 8. The at least one threaded key 8 may include or form internal threads corresponding to external threads of the threaded rod assembly 25. The post assembly 110 may be used to enable at least one threaded key 8 (e.g., two opposing threaded keys 8,8) to be manually moved in and out in a radial manner (e.g., relative to axis X-X) to engage and disengage the threaded rod assembly 25.

As shown in fig. 11, the actuation of the at least one threaded key 8 may be achieved by rotation of the outer sleeve 6 (e.g. manually rotatable about the axis X-X). At least one threaded key 8 may be disposed within at least one corresponding opening in the abutment body 5, and the outer sleeve 6 may be disposed through the eccentric bore around the at least one threaded key 8, the abutment body 5, and the threaded rod assembly 25. The eccentric hole may include a cam surface such that when the sleeve 6 is rotated (e.g., about axis X-X), the cam surface enables the at least one threaded key 8 to move away from and disengage the threaded rod assembly 25 via the respective resilient member 10, or the at least one threaded key 8 to engage the threaded rod assembly 25 (i.e., the first strut screw 12 and/or the second additional strut screw 13). As also shown in fig. 11, the strut assembly 110 may further include at least one radial pin 2 and a sleeve 6 provided with corresponding slots, whereby the strut assembly 110 may control the positioning of the sleeve 6 relative to the strut 5. The at least one groove may comprise at least one axially extending recess corresponding to a position of the at least one pin 2 (and thus of the sleeve 6 itself) in which the at least one key 8 is forced into engagement with the threaded rod assembly 25 by the sleeve 6, and/or to a position of the at least one pin 2 (and thus of the sleeve 6 itself) in which the at least one key 8 is forced out of engagement with the threaded rod assembly 25 by the at least one spring 8. As shown in fig. 11, the strut assembly 110 may include a resilient member 9, the resilient member 9 for axially biasing the sleeve 6 such that the at least one pin 2 is biased into the at least one axially extending recess of the at least one slot.

Rotation of the threaded rod assembly 25 relative to the support post 5, or rotation of the support post 5 relative to the threaded rod assembly 25, while the at least one threaded key 8 engages the threaded rod assembly 25 thereby producing a forced translation of the support post 5 relative to the threaded rod assembly 25 (or vice versa), thereby lengthening or shortening the support post assembly 110. When at least one threaded key 8 is disengaged from threaded rod assembly 25, threaded rod assembly 25 is free to move (axially along axis X-X and rotationally about axis X-X) within support column 5 so that the length of support column assembly 110 can be freely and quickly adjusted.

While the at least one threaded key 8 and the outer sleeve 6 of the post body 5 allow for selective length adjustment of the post 110 (i.e., the axial X-X length between the joint of the threaded rod assembly 25 and the joint of the post body 5 may be adjusted, thereby adjusting the distance and direction between the first platform 120 and the second platform 130), the system 100 may also be used to adjust the length (e.g., the length along the axis X-X) of the threaded rod assembly 25 (and/or the post body 5), thereby allowing for adjustment of the overall adjustable range of the system 100. In some embodiments, the system 100 may be used to adjust the overall possible length of the strut 110 (and/or strut 5) without requiring the strut 110 to be detached/disconnected from the platforms 120,130, or otherwise interfering with the in situ operation (functioning) of the strut 110.

As shown in fig. 12 and 13, in some embodiments, the system 100 may be used to selectively extend the threaded rod assembly 25 without requiring the support post 110 to be detached/disconnected from the platforms 120,130 or otherwise interfering with the in situ operation of the support post 110. For example, as shown in fig. 11, the first strut screw 12 of the threaded rod assembly 25 shown in fig. 1-11 has been extended by the second additional strut screw or threaded rod 13. The threaded rod assembly 25 may be extended by using at least one additional threaded rod 13, the additional threaded rod 13 including external threads substantially identical to the external threads of the pre-existing component of the threaded rod assembly 25 (the first stud screw 12), and the additional threaded rod 13 may be substantially similar to the pre-existing component of the threaded rod assembly 25. For example, the at least one additional threaded rod 13 may comprise the same pitch as the external thread of the first stud screw 12 of the threaded rod assembly 25. At least one additional threaded rod 13 (and/or a pre-existing part of the threaded rod assembly 25 forming its free end, such as the first stud screw 12) may include provisions for ensuring matching of the respective pitches so that the compound pitch maintains a continuous end configuration on the connecting rod.

The threaded rod assembly 25 may be extended by the additional threaded rod 13 in a variety of ways. In one example (not shown), the threaded rod of the threaded rod assembly 25 may include a cap screw concentrically disposed and placed within a central channel of the additional threaded rod 13. The additional threaded rod 13 may be used such that a cap screw protrudes from the end of the additional threaded rod 13, while the head of the cap screw is retained or placed within the cavity. The existing first threaded shaft 12 may include a threaded concentric bore (tapped bore) for threadably coupling with the exposed portion of the cap screw. To receive additional threaded rods 13 to further lengthen the threaded rod assembly 25, the pre-installed additional threaded rods 13 may be used to receive threaded inserts behind cap screws placed in the cavities. The threaded insert may comprise a concentric threaded hole for receiving the cap screw of the next additional threaded rod 13. In this way, any number of additional threaded rods 13 may be added in situ on the threaded rod assembly 25.

As another example (not shown), a threaded turnbuckle may be used as a connecting element between an in-situ or pre-installed threaded rod (e.g., the first threaded rod 12 of the pre-installed additional threaded rod 13) and the additional threaded rod 13. The threaded turnbuckle is adapted to threadedly engage with internal threads of the central passage of the pre-installed threaded rod (e.g., first threaded rod 12) and additional threaded rod 13. The turnbuckle may include a first portion having a right-hand external thread and a second portion having a right-hand external thread. The turnbuckle may also include a socket (sokect) or another suitable driving feature coupled to one end for transmitting torque to the turnbuckle. In such an embodiment, the internal thread of the in-situ or pre-installed threaded rod may comprise a pitch having the same thread direction as the thread direction on the opposite end of the turnbuckle's drive part, wherein the additional threaded rod 13 has the same thread direction as the end of the turnbuckle having the drive part. The drive element may be inserted down a central channel in the additional threaded rod 13 and engage with the drive feature of the turnbuckle. When on the shaft of the drive element and the drive part of the turnbuckle is engaged with the drive element, the additional threaded rod 13 may be arranged coaxially with the in-situ or pre-mounted threaded rod and turnbuckle, which is in turn twisted and screwed into the in-situ or pre-mounted threaded rod and the additional threaded rod 13. The synchronization of the threads of the external threads of the in-situ or pre-mounted threaded rod and the additional threaded rod 13 can be achieved by interacting parts at the mating ends of the in-situ or pre-mounted threaded rod and the additional threaded rod 13.

As another example, as shown in fig. 11 and 12, the system 100 may include a turnbuckle connection element 22, the connection element 22 providing or allowing some pre-assembly means so that the additional threaded rod 13 and the connection element 22 do not require separate handling during installation. Similar to the turnbuckles described above, connecting element 22 may be used to threadingly engage internal threads 58 of the central passages of the pre-installed threaded rod (e.g., first threaded rod 12) and additional threaded rod 13. The connecting element 22 may include a first portion 60 having external threads with a first pitch and a second portion 61 having external threads with a second pitch different from the first pitch. For example, the first pitch may be a fine pitch and the second pitch may be a coarse pitch (or vice versa). Although the pitch of the external thread of the first portion 60 may be different from the pitch of the external thread of the second portion 61, the thread direction may be the same. As such, the internal thread 58 of the pre-installed threaded rod 12 may include at least the first or second pitch (and corresponding thread direction) at the first end of the pre-installed threaded rod 12, and the internal thread 58 of the additional threaded rod 13 may include at least the other of the first or second pitch (and corresponding thread direction) at the first end of the additional threaded rod 13.

The internal thread of the second end of the additional threaded rod 13 opposite to its first end may have the same pitch as the first end of the other first or second pitch. Thus, the second end of the additional threaded rod 13 may allow additional threaded rods 13 to be installed to further lengthen the threaded rod assembly 25, thereby further increasing the home position range of the threaded rod assembly 25.

In some embodiments, the internal thread 58 of the pre-installed threaded rod 12 may comprise a coarse pitch and the internal thread 58 of the additional threaded rod 13 may comprise a fine pitch (or vice versa). In such an embodiment, if the connecting element 22 is twisted in a first rotational direction and is threadedly engaged with the internal threads 58 of the pre-installed threaded rod 12 and the additional threaded rod 13, respectively, the connecting element 22 will move out of the additional threaded rod 13 at a given rate as the additional threaded rod 13 rotates, while the connecting element 22 will enter the pre-installed threaded rod 12 at a relatively faster rate, thereby differentially bringing the additional threaded rod 13 into contact with the pre-installed threaded rod 12. The connecting element 22 may include a socket or another suitable drive feature 62 incorporated into one end for transmitting torque to the connecting element 22 (e.g., through the channel of the pre-installed screw 12).

In this way, the connecting element 22 may be used to couple the additional threaded rod 13 to the pre-installed threaded rod 12 without disconnecting the pre-installed threaded rod 12 or otherwise disturbing the pre-installed threaded rod 12 (i.e., may be installed in situ). In some embodiments, the connecting element 22 may be screwed into engagement with the additional threaded rod 13, and the additional threaded rod 13 may include an inclined internal thread that is thinner than the pre-installed threaded rod 12 (or vice versa). As shown in fig. 12, connecting element 22 may include a non-threaded region 63 between first portion 60 and second portion 61. The non-threaded region 63 may allow the

finer pitch portion

60 or 61 of the connecting element to be initially partially over-threaded to either of the additional threaded rod 13 and the pre-installed threaded rod 12 (which includes a finer oblique internal thread).

For example, fig. 13-17 illustrate the first pre-installed threaded rod 12 and the second or additional threaded rod 13 being placed together and coupled together. As noted above, although the two threaded rods of the extraosseous fixation system are used to illustrate one exemplary use of connecting element 22, connecting element 22 may be used to place together (or separate) and couple together any two components or parts, whether part of the extraosseous fixation system or part of other orthopedic or non-orthopedic mechanisms or systems. Further, while connecting element 22 is depicted and described as having

external threads

60,61 and first and

second rods

12, 13 have mating internal threads, connecting element 22 may have internal threads and the aforementioned components may have external threads.

As shown in fig. 13-14, initially the second rod or member 13 and the connecting element 22 may be threadably coupled by relatively fine pitch threads and rotated or twisted together (e.g., by a tool) to threadably engage the first rod or member 12 by relatively coarse pitch threads. In such embodiments, the unthreaded portion 63 of connecting element 22 may extend between first rod or member 12 and second rod or member 13. As shown in fig. 14, the second rod or member 13 and the connecting element 22 may be rotated together as a unit until the first rod or member 12 meets the second rod or member 13, thereby preventing relative rotation between the first rod or member 12 and the second rod or member 13. As shown in fig. 15 and 16, the connecting element 22 may be further rotated such that the connecting element 22 travels axially through the first rod or member 12 and the second rod or member 13. However, as shown in fig. 16 and 17, since the pitch of the threaded connection between the connecting element 22 and the second rod or member 13 is finer than the pitch of the threaded connection between the connecting element 22 and the first rod or member 12, the connecting element 22 travels slower or a shorter distance when rotated by the second rod or member 13 than when rotated by the first rod or member 12. In this way, the connecting element 22 may draw the first rod or member 12 and the second rod or member 13 together, for example, for an arrangement in which the external threads of the first rod or member 12 and the second rod or member 13 are aligned or continuous. It should be noted that the combination of the relatively fine pitch threads of the connecting element 22 and the second rod or member 13, and the relatively coarse pitch threads of the connecting element 22 and the first rod or member 12, respectively, provides extremely high axial accuracy or adjustment between the first rod or member 12 and the second rod or member 13, which may not be possible with a single pitch due to physical limitations (i.e., this case where the pitch is equal to the difference in pitch between the fine and coarse pitches may not be possible in reality).

The connecting element 22 can be arranged or preassembled with the additional threaded rod 13 before being coupled to the preassembled threaded rod 12. In order to make most effective use of the engaging thread of the connecting element 22 in the additional threaded rod 13, the additional threaded rod 13 and/or the connecting element 22 can be used such that the additional threaded rod 13 and the connecting element 22 rotate together when the connecting element 22 is screwed into the pre-installed threaded rod 12.

As shown in fig. 18, at least the free end of the preinstalled threaded rod 12 and both ends of the additional threaded rod 13 may include a keying element 53 for ensuring proper mating of the external threads between the preinstalled threaded rod 12 and the ends of the additional threaded rod 13. In use, the first portion 60 of the connecting element 22 may be pre-installed in the passage of the additional threaded rod 13, and the second portion 61 of the connecting element 22 may thereby extend from the additional threaded rod 13. The additional threaded rod 13 and the connecting element 22 may be twisted (e.g., rotated together as a unit) such that the second portion 61 of the connecting element 22 threadedly engages the internal threads of the cavity 28 of the pre-installed threaded rod 12, thereby advancing axially into the pre-installed threaded rod 12 and drawing the additional threaded rod 13 and the pre-installed threaded rod 12 together. As shown in fig. 18, the wedge members 53 of the additional threaded rod 13 and the wedge members 53 of the pre-installed threaded rod 12 may be used such that when the mating surfaces of the wedge members 53 are within an optimal distance of each other, the mating surfaces of the wedge members 53 contact each other to prevent relative rotation between the additional threaded rod 13 and the pre-installed threaded rod 12.

As also shown in fig. 18, in such embodiments, the wedge-shaped elements 53 of the additional threaded rod 13 and the wedge-shaped elements 53 of the pre-installed threaded rod 12 may include grooves 54 corresponding to mating surfaces, the grooves 54 allowing relative axial translation between the additional threaded rod 13 and the pre-installed threaded rod 12. In this state, the drive part 62 of the connecting element 22 can be engaged by the passage of the additional threaded rod 13 and rotated such that the connecting element 22 can be translated in a threaded manner at different rates through the cavity of the additional threaded rod 13 and the cavity of the pre-mounted threaded rod 12, so that the additional threaded rod 13 and the pre-mounted threaded rod 12 are translated axially towards one another. As shown in fig. 18, the connecting element 22 can be twisted until the mating face 56 of the additional threaded rod 13 and the mating face 56 of the pre-installed threaded rod 12 come into contact with one another. As shown in fig. 18, the additional threaded rod 13 and the pre-mounted threaded rod 12 may be used such that when the mating end surfaces 56 of the wedge elements 53 of the additional threaded rod 13 and the mating end surfaces 56 of the pre-mounted threaded rod 12 are engaged, the additional threaded rod 13 and the pre-mounted threaded rod 12 are firmly or rigidly coupled and the pitches of the external threads of the additional threaded rod 13 and the pre-mounted threaded rod 12 are properly synchronized.

As fig. 12 to 17, the free end of the pre-mounted threaded rod 12 or of the additional threaded rod 13 (in the case of mounting) may comprise a guide bushing 14, which guide bushing 14 is intended to cooperate with the wedge element 53, the mating end face 56 and/or the recess of the wedge element 53. The guide bushing 14 may be used to provide a relatively smooth surface for contacting the interior of the lumen of the abutment 5, thereby protecting the external threads of the abutment 5. As also shown in fig. 12, the guide bushing 14 can be fixed (in the case of installation) to the free end of the pre-installed threaded rod 12 or the additional threaded rod 13 with the cap screw 3.

Although the connecting element 22 is described and used above for the first preinstalled threaded rod 12 and the second additional threaded rod 13 of the strut assembly, the text expressly and specifically contemplates: the connecting element 22 may be used with any other first and second members. In some embodiments, the first and second members coupled and combined together by connecting element 22 may not be associated with a strut assembly, nor with a 6DOF bone or tissue fixation system. In other words, the first member and the second member coupled and combined together by the connecting element 22 may be any first member and second member for coupling by the connecting element 22. For example, the connecting element 22 (in which first and second threaded portions of different pitches are separated by a non-threaded portion) may be internally or externally threaded for engagement with respective threaded first and second members. It should also be noted that the double-threaded nature of connecting element 22 with different pitches (e.g., through a combination of pitches) provides a higher level of accuracy of axial movement between the first and second members, produces improved mechanical advantage over other mechanisms that couple and combine the first and second members together, produces a greater torque so that the first and second members remain tightly coupled, and the construction is substantially unaffected by vibration.

As shown in fig. 3-7 and 19, the pre-installed threaded rod 12 of the threaded rod assembly 25 of the strut 110 may include a cross pin 18 adjacent the strut body 5, the cross pin 18 being manually engageable and used to apply torque to the threaded rod assembly 25. In this manner, assuming that the buttress body 5 is threadably engaged with the external threads of the threaded rod assembly 25, the cross pin 18 may be utilized in situ to adjust the length of the buttress 110, thereby adjusting the distance and direction between the first platform 120 and the second platform 130 (and, thus, the bone or tissue segments coupled to the first platform 120 and the second platform 130).

As described above, the strut 5 of the strut assembly 110 may include a joint with the first platform 120 or the second platform 130 for rotating the strut 5. As shown in fig. 14-18, the abutment 5 may include a knob 15 formed or coupled to one end or end of the abutment 5. As shown in fig. 19, the knob 15 may include one or more holes 26. As shown in fig. 19, the joint of the strut 5 of the strut assembly 110 may include a first cylindrical joint 7, the first cylindrical joint 7 including a spherical cavity for receiving the spherical protrusion 15 of the strut 5 and mating with the spherical protrusion 15 of the strut 5. The barrel joint 7 may include one or more apertures 28 that may extend therethrough. The joint of the abutment body 5 may further comprise at least one pin 24, the at least one pin 24 being adapted to extend through a corresponding hole 28 of the cylindrical joint 7 and a corresponding hole 26 of the knob 15. In this way, as shown in fig. 19, at least one pin 24 can limit the rotation of the knob 15 of the abutment 5 within the cylindrical joint 7 about one axis X3-X3, thus forming a universal joint.

As shown in fig. 14-18, the barrel joint 7 may also be used to removably and rotationally mate or attach the first platform 120 and the second platform 130. As shown in fig. 15-18, the first platform 120 and the second platform 130 may include a stud 50 extending therefrom for defining a free end. The studs 50 may be arranged in closely spaced pairs and disposed about the circumference of the first platform 120 and the second platform 130. In some embodiments, the studs 50 may extend radially, such as radially perpendicular to the axis X2-X2 and/or radially along a plane defined by the

respective platforms

120, 130. As shown in fig. 15, the stud 50 may be generally cylindrical, but may include a flat portion 52. The flat portion 52 may be a planar chord (chord) that engages two portions of the cylindrical outer surface of the stud 50. Each stud 50 may also include a recess or groove 52, the recess or groove 52 extending at least substantially circumferentially around the outer surface between its free end and the respective first platform 120 or second platform 130. The circumferential groove 52 may thus form a head of the stud 50 with the substantially cylindrical outer surface and the flat portion 52.

As shown in fig. 16-18, the barrel joint 7 may include an opening or cavity shaped and dimensioned to receive the stud 50 of the first or second platform therein. As also shown in fig. 16-18, the barrel joint 7 may include a dowel or other feature 1, the dowel or other feature 1 extending through a portion of the opening or cavity of the barrel joint 7. The openings or cavities of the barrel knuckle 7 and dowel pin 1 may be formed in the same shape and configuration as the stud 50, such as the cylindrical outer surface and flat portion 52 of the stud 50 described above.

In this manner, as shown in fig. 16 and 17, the strut 110 may be oriented such that the barrel joint 7 and pin 1 may be aligned with and slide over the cylindrical outer surface of the stud 50 and flat portion 52, respectively. As shown in fig. 17, pin 1 may be aligned with groove 52 of stud 50 and post 110 may be rotated such that pin 1 is no longer aligned with flat portion 52 and is thus positioned in groove 52 behind the head of stud 50. Thus, rotation of the strut 110 may cause the joint of the threaded rod assembly 25 to align with the corresponding stud 50 of the other of the first platform 120 and the second platform 130, or at least to be positioned closer to the corresponding stud 50 of the other of the first platform 120 and the second platform 130. Thus, the joint allows at least some relative rotation between the support column 110 and the

respective platform

120, 130. Thus, the joints provide rotation between the column 110 and the respective platforms 120,130 about two mutually perpendicular axes of rotation.

In this way, the joint of strut 5 may be a rotary joint made of the native parts of platforms 120,130 and other native parts of strut assembly 110. The joint does not provide a full 360 degree rotation, but the flat portion 52 of the stud 50 may be oriented so as to provide a range of relative rotation between the stud 50 and the post 110, such as an amount or range of relative rotation required or encountered during normal operation of the system 100. Accordingly, the joint is assembled with over-rotation of strut assembly 110 beyond the normal or expected operable range of strut assembly 110. Since the strut assembly 110 must be attached at both ends, one end connected to the first platform 120 and the other end connected to the second platform 130, the connection configuration is sufficient for a first connection to one of the first platform 120 or the second platform 130, while the rest of the strut assembly 100 may not be within operable range during the attachment process.

As shown in fig. 19, since the studs 50 are substantially identical to one another, the joint of the threaded rod assembly 25 may mimic the "out of operable rotation" feature of the joint (or an operatively equivalent joint) of the abutment 5. The end of the pre-installed screw 12 of the threaded rod assembly 25 may include or form a strut screw 12 with a ball joint 11 secured to the strut screw 12. The end of the strut screw 12 may be threaded and the brake ring 16 and wave spring 23 may be housed between the end cap 17 (which is threaded to the external threads) and the ball joint 11. The end cap 17 and the brake ring 16 may be rotationally coupled or fixed to each other. The ball joint 11 may include a series of detents adjacent the brake ring 16 and the wave spring 23 may force the brake ring 16 to detent. The ball joint 11 may also include at least one hole for receiving at least one pin 24 therethrough. As shown in fig. 19, at least one pin 24 may rotationally fix the ball joint 11 with the cavity of the helical joint 15. As explained further below, the helical joint 15 may be coupled to the stud 50 of one of the first platform 120 and the second platform 130. In this way, rotation of the threaded rod assembly 25 (e.g., via the cross pin 18) may thereby rotate the brake ring 16 relative to the threaded joint 15 to provide a visual and/or sensory indication of the rotational movement and/or position of the threaded rod assembly 25.

The helical joint 15 of the joint of the threaded rod assembly 25 of the strut assembly 110 may include a spherical cavity for receiving the spherical joint 11 of the threaded rod assembly 25 and mating with the spherical joint 11, as shown in fig. 19. As described above, the at least one pin 24 may extend into the threaded knuckle 15 and the helical knuckle 15, which may limit rotation of the spherical knuckle 11 of the threaded rod assembly 25 within the helical knuckle 15 about the axis X4-X4 (as shown in fig. 19), thereby forming a universal joint.

As also shown in fig. 19, the helical joint 15 of the joint of the threaded rod assembly 25 of the strut assembly 110 may include an opening or cavity shaped and dimensioned to receive the stud 50 of the first platform 120 or the second platform 130 therein. As also shown in fig. 19, the helical joint 15 may include a pin or other feature 19. The pin 19 may be disposed within a groove or slot for enabling the pin 19 to move between a position such that the pin 19 extends through a portion of the opening or cavity of the screw joint 15 and a position such that the pin 19 does not extend through a portion of the opening or cavity of the screw joint 15.

As shown in fig. 19, the joint of the threaded rod assembly 25 of the strut assembly 110 further includes a knob 20, a push pin 21, and a ball 4. Knob 20 may include an inner surface forming a cam for translating push pin 21 into, then through helical joint 15, and then into pin 19. In this way, the strut 110 is connected to one of the first and second platforms 120,130 by the joint of the strut body 5, the strut 110 may be oriented such that the threaded knuckle 15 of the joint of the threaded rod assembly 25 aligns with and slides the cylindrical outer surface of the stud 50 and the flat portion 52. The pin 19 may be aligned with the groove 52 of the stud 50 and then the knob 20 may be rotated so that the cam of the knob 20 pushes the push pin 21 into the pin 19 so that the pin 19 extends through a portion of the opening or cavity of the helical knuckle 15 and is located within the groove 52 behind the head of the stud 50. Ball 4 may be positioned adjacent push pin 21 and prevent further rotation of knob 20 from this "locked" position. In this manner, the joint of the threaded rod assembly 25 may be a rotary joint made from the native parts of the platforms 120,130 and other native parts of the strut assembly 110.

Fig. 20-59 illustrate an additional 6DOF bone or tissue fixation system and associated fixation method 200, the system and method 200 having the desired stability and mobility characteristics of a hexapod system without the need for time-consuming strut length selection and assembly difficulties. The 6DOF bone or tissue fixation system and associated fixation method 200 shown in fig. 20-59 is similar to the 6DOF bone or tissue fixation system and associated fixation method 100 shown in fig. 1-19. Accordingly, like reference numerals preceded by a "2" are used to indicate like aspects or functions, and the above description of aspects or functions of the system and method 100 (and alternative embodiments thereof) applies equally to the system and method 200. As shown in fig. 20 to 44B, the system 200 differs from the system 100 in that the respective strut assemblies 210 (six strut assemblies 210) are connected to each other as a single unit 315 before being attached to the first and second platforms 220 and 230 (refer to fig. 20 to 31) and after being attached to the first and second platforms 220 and 230 (refer to fig. 32 to 44B). As explained further below, the ends of strut assemblies 210 include a live joint or coupling that allows some relative movement between the paired strut assemblies 210 and prevents strut assemblies 210 from disconnecting from each other. In this manner, as shown in fig. 20-31, the six strut assemblies 210 form a single construct, unit or structure 215. A single construction 215 of six individually and movably coupled strut assemblies 210 (as shown in fig. 20-31) allows for quick and easy control and attachment to a first platform 220 and a second platform 230 (as shown in fig. 32-44B). For example, rather than separately obtaining, assembling and/or adjusting six strut assemblies 201, then independently attaching the six strut assemblies 201 to each other and then to the first and

second platforms

220, 230, as in fig. 32-44B, a single construct 215 of six movably linked strut assemblies may be obtained and adjusted to a single unit as shown in fig. 20 and 31, and quickly and easily coupled to the first and

second platforms

220, 230.

As shown in fig. 45-48, 50, 58, and 59, a single construct 215 of six strut assemblies 210 may be formed from a movable joint or coupling mechanism that couples opposing ends of adjacent strut assemblies 210. Such a movable joint may be any joint that allows movement relative to the first platform 220 or second platform 230 to which it is attached and relative movement of the adjacently engaged strut assembly 210 to allow or provide movement and/or angle (as shown in fig. 41-44B) between the first platform 220 or second platform 230. The exemplary movable joint shown in fig. 45-48, 50, 58, and 59 includes a base knuckle 201, the base knuckle 201 rigidly secured to a strut barrel 205 by a post of a knuckle pivot 204. The posts of the joint pivot 204 may be located in corresponding holes in the base joint 201 and may extend. In this manner, the joint pivot 204 may be rotationally coupled to the base joint 201 about an axis extending perpendicular to the strut barrel 205. As shown in fig. 45-48, 50, 58, and 59, the first or main strut screw 212 can be pivotally coupled to the pivot yoke 230A by a spring pin 213. The first strut screw 212, the pivot yoke 230A and the spring pin 213 serve to enable the first strut screw 212 and the pivot yoke 230A to be pivotally coupled about an axis (spring pin 213) extending perpendicular to the screw 212.

As shown in fig. 45-48, 50, 58, and 59, pivot yoke 230A and joint pivot 204 may be rotatably coupled to one another by shoulder screws 202, the shoulder screws 202 extending through holes in the shoulder of the joint pivot 204 that are substantially aligned along the long axis and spaced apart. The pivot yoke 230A may be positioned between the shoulders of the joint pivot 204 such that the pivot yoke 230A is sandwiched therebetween along the long axis of the strut barrel 205, and the shoulder screw 202 may also pass through a hole in the pivot yoke 230A. In this manner, the shoulder screw 202 may extend through one shoulder of the joint pivot 204, then through the pivot yoke 230A, and then finally through the other shoulder of the joint pivot 204. Thus, joint pivot 204 and pivot yoke 230A may be rotatably coupled to each other about an axis defined by shoulder screw 202. The shoulder screw 202 may be prevented from sliding out of the bore of the shoulder of the joint pivot 204 and the bore of the pivot yoke 230A by a pin (not shown) in a groove or the like of the shoulder screw 202 that extends through the pivot yoke 230A and through at least a portion of the shoulder screw 202.

For example, as shown in fig. 45-49, the movable engaging or coupling ends (as described above) of pairs or adjacent strut assemblies 210 may be quickly and easily secured or coupled to the first and

second platforms

220, 230. In this way, a single construct 215 of six strut assemblies may be quickly and easily secured or coupled to the first platform 220 and the second platform 230. For example, as shown in fig. 45-49, the shoulder screw 202 may include a threaded portion 275, the threaded portion 275 extending beyond the distal shoulder of the joint pivot 204. In this way, in the unattached state, the threaded portion 275 of the shoulder screw 202 can freely form a free end. Thus, for example, the threaded portion 275 of the shoulder screw 202 may be aligned with and threaded into a mating hole or fixation point 270 in the first platform 220 or the second platform 230 to couple the movable joint between the pair of strut assemblies 210 to the first platform 220 or the second platform 230 (as shown in fig. 47 and 48).

For example, as shown in fig. 51-59, the length adjustment mechanism of strut assembly 210 is different from the length adjustment mechanism of strut assembly 110. As shown in fig. 51-59, the gasket 208 may be seated within a cavity of the strut cylinder 205 or a base of the housing. As shown in fig. 51, 53, 56, 58, and 59, the nut 206 may also be positioned within the cavity or housing of the strut cylinder 205 and over the washer 208. The nut 206 is sized smaller than the lumen of the strut barrel 205 such that the nut 206 is capable of moving radially (e.g., concentric or eccentric to the lumen and/or long axis) relative to the strut assembly 210 or the long axis of the strut barrel 205. As shown in fig. 51, 53, and 56A-57B, the nut 206 may include an eccentric hole 288 and a concentric inner threaded portion 287 (or vice versa).

For example, as shown in fig. 51, 53, 58, and 59, the nut 206 may include a radially or laterally extending groove 280b formed in a top or upper surface of the nut 206. The nut 206 may also include a first locating pin hole or aperture 283 that extends partially through the nut 206 along the long axis of the strut assembly 210 or strut barrel 205. The nut 206 may also include at least an extending second dowel hole or aperture 284 that extends partially through the nut 206 along the long axis of the strut assembly 210 or strut barrel 205. The spring 218c and pin or peg 217 may be positioned within the second pin hole 284 such that the pin 217 is offset from the second pin hole and is located at the top surface of the nut 206. However, the spring 218c may include sufficient travel so that the pin 217 may be forced further (as compared to its natural or neutral position) into the second locating pin hole 284.

As further shown with reference to fig. 51, 53, 58, and 59, for example, the adjustment knob 207 may be partially positioned within the cavity or housing of the strut barrel 205 above the nut 206. The adjustment knob 207 may be rotatably coupled to the strut barrel 205 by a plurality of pins 216, the plurality of pins 216 extending radially through the strut barrel 205 and into concentric grooves within the portion of the adjustment knob 207 located within the strut barrel 205. In this manner, the adjustment knob 207 may be manually rotated about the long axis of the strut assembly 210 or the strut barrel 205, for example. To control and/or provide an indication of the relative angular position orientation of the adjustment knob 207 with respect to the strut barrel 205, the plurality of balls 215 may be biased by an extended spring 218 a. The ball 215 may be biased by a spring 218a into a corresponding hole or notch 286 formed in the bottom surface of the adjustment knob 207 (see fig. 52).

As shown in fig. 52, the bottom surface of the adjustment knob 207 may also include a radially or laterally extending groove 280b that corresponds to the radially or laterally extending groove 280b in the top surface of the nut 206. As shown in fig. 51, 52, and 59, the compression spring 218b may be positioned between the radially or laterally extending groove 280b of the nut 206 and the radially or laterally extending groove 280b of the adjustment knob 207 and partially within the groove 280 b. The compression spring 218b, the radially or laterally extending groove 280b of the nut 206, and the radially or laterally extending groove 280b of the adjustment knob 207 may serve to naturally or neutrally bias the nut 206 within the cavity of the strut barrel 205 to be eccentric relative to the long axis of the strut assembly 210 or the strut barrel 205. As shown in fig. 56B and 57B, the nut 206 may be naturally or neutrally biased such that the eccentric bore 288 of the nut is aligned with (i.e., concentric with) the long axis of the strut assembly 210 or strut barrel 205 and the first strut screw 212 or second strut screw 213 extending through the nut 206. In this manner, as shown in fig. 56B and 57B, the concentric threaded portion 287 of the nut 206 may naturally be offset or spaced apart from the first or second strut screws 212, 213 extending through the nut 206.

To allow the nut 206 to be repositioned laterally or radially away from its natural position such that the concentric threaded portion 287 of the nut 206 is concentric and engaged with the first or second post screw 212, 213 (as shown in fig. 56A and 57A), the pin 217 may be engaged within a lateral or radial groove 285 (as shown in fig. 52 and 56A-57B) in the underside of the adjustment knob 207. When the threaded portion 287 of the nut 206 is concentric with the first or second post screws 212, 213 and is engaged with the first or second post screws 212, 213 (as shown in fig. 56A and 57A), rotation of the adjustment knob 207 may rotate the nut 206 such that the threaded portion 287 of the nut 206 rotates relative to the first or second post screws 212, 213 to translate the post barrel 205 (and components of the length adjustment mechanism) relative to the nut 206 and lengthen or shorten the post assembly 210.

As shown in fig. 54 and 56A-57B, the radial groove 285 of the adjustment knob 207 corresponding to the pin 217 axially biased by the spring 218c may include a hole or recess 292 that receives the corresponding pin 217 therein. The length adjustment mechanism may be used such that when the threaded portion 287 of the nut 206 is concentric with the first or

second post screw

212 or 213 and engaged with the first or

second post screw

212 or 213, the hole or recess 292 and the corresponding pin 217 are aligned and the spring 218c naturally biases or positions the respective pin 217 within the hole or recess 292. As shown in fig. 54, 55, and 56A-57B, the adjustment knob 207 may include an access hole that allows access to the hole or recess 292, thereby allowing the respective pin 217 to manually remove the respective pin 217 from the hole or recess 292, thereby allowing the nut 206 to naturally bias by the compression spring 218B off-center from the first or

second strut screw

212, 213, and the concentric threaded portion 288 to be spaced apart (i.e., disengaged) from the first or

second strut screw

212, 213.

As shown in fig. 56B and 57B, the length adjustment mechanism may initially be set such that in the natural state of the nut 206, the nut 206 is biased by a compression spring 218B that is eccentric to the first or

second post screw

212, 213 such that the concentric threaded portion 288 is spaced apart (i.e., disengaged) from the first or second post screw 212, 213 (and the eccentric hole 287 is concentric with the first or second post screw 212, 213). The strut casing 205 may include an access bore 299, the access bore 299 extending radially through the strut casing 205 to an outer surface of the nut 206 (as shown in fig. 55-57B and 59). Thus, the access hole 299 may allow for insertion of a member (not shown) through the access hole 299 and radial or lateral translation or movement of the nut 206 relative to the strut cylinder 205 within the lumen of the strut cylinder 205. It should be noted that a transverse or radial groove 285 on the underside of adjustment knob 207 will allow nut 206 and pin 217 to translate or move radially or transversely relative to adjustment knob 207. The nut 206 may be translated radially or laterally (via the access hole 299) until the pin 217, biased by the spring 218c, is aligned with and thus biased in the hole or recess 292 in the corresponding groove 285 of the adjustment knob 207 (as shown in fig. 56A and 56B). In this manner, the eccentric threaded portion 288 of the nut 206 may translate laterally or radially from disengaging with the first or second strut screw 212, 213 (as shown in fig. 56B and 57B), to changing into engaging with the first or second strut screw 212, 213 (as shown in fig. 56A and 57A), and the eccentric threaded portion 288 of the nut 206 may be releasably secured in this arrangement. Accordingly, rotation of the adjustment knob 207 may rotate the nut 206 such that the threaded portion 287 of the nut 206 rotates relative to the first or second strut screws 212, 213 to translate the strut barrel 205 (and components of the length adjustment mechanism) relative to the nut 206 to lengthen or shorten the strut assembly 210.

Fig. 60-87 illustrate an additional 6DOF bone or tissue fixation system and associated fixation method 300, the system and method 300 having the desired stability and mobility characteristics of a hexapod system without time consuming strut length selection and assembly difficulties. The 6DOF bone or tissue fixation system and related fixation method 300 shown in fig. 20-59 is similar to the 6DOF bone or tissue fixation system and related fixation method 100 shown in fig. 1-19, and the 6DOF bone or tissue fixation system and related fixation method 200 shown in fig. 20-59. Accordingly, like reference numerals preceded by a "3" are used to indicate like aspects or functions, and the description above with respect to the system and method 100 and aspects or functions of the system and method 200 (and alternative embodiments thereof) is equally applicable to the system and method 300.

As shown in fig. 60-68, system 300 differs from system 100 and system 200 in that system 300 includes fiducial markers or markings 307 as points of reference and/or measurement. Fiducial markers 307 may be used to help identify and/or control the orientation of each strut-platform joint and the length of each strut. For example, the first platform 320 of the system 300 may be coupled to a first bone segment and the second platform 330 of the system 300 may be coupled to a second bone segment, and the system 300 may be controlled, i.e., moved, such that the first bone segment is aligned with the second bone segment at a desired location. The alignment may be changed over time to complete the deformity correction process. One of the bone segments may be a reference segment. Another bone segment (mobile segment) may be moved to align with the reference segment. The fiducial markers 307 of the system 300 may be used to identify the position and/or orientation of the strut assembly 310 (e.g., through clinical assessment and/or imaging) as shown in fig. 60-68 for use in a method or process for using the strut to achieve a desired or desired bone segment orientation. In some embodiments, the fiducial markers 307 of the system 300 may be used to identify the location and/or orientation of the coupling mechanisms provided at the ends of the pairs of struts 310 to couple the struts 310 to the respective platforms 320,330 (as shown in fig. 60-68), and thus the struts 310 themselves are used by extrapolation to a method or process for using the struts to achieve a desired or desired bone segment orientation. In this manner, the indicia 307 may be used in a method or process of the system 300 for using the strut 307 to achieve a desired or desired orientation of a bone segment, such as the method or process disclosed in U.S. patent No.8,419,732, which is incorporated herein in its entirety. In some embodiments, the method or process may utilize the marker 307 to determine a "current" position and/or orientation of the strut 307 and a "corrected" position and/or orientation of the strut. In some embodiments, the method or process may determine how the markings 307 (and thus the respective strut 310) should be positioned and/or oriented in situ.

As shown in fig. 60-71 and 75-78, the marker 307 may be a spherical knob or head of a shoulder screw 302, the shoulder screw 302 being coupled with an attachment base 303, the attachment base 303 coupling a pair of adjacent strut assemblies 310 to

respective platforms

320, 330. In this manner, as further explained below, the markings 307 may be used to twist the shoulder screws 302 to threadably detachably couple the coupling base 303 (and thus the strut assembly 310 coupled to the coupling base 303) to the

respective platforms

320, 330. The markings 307 may be positioned external to the system 300, such as past the outer ends of the

respective platforms

320, 330. The marker 307 may be adapted to be visually visible upon imaging, such as upon X-ray exposure. Indicia 307 may include at least one indicia that is visually distinct to some extent from other indicia 307. For example, as shown in fig. 60-71 and 75-78, marker 307 includes a unique relatively small spherical marker at one end of system 300, at a location or position on

respective platforms

320, 330. The unique mark 307 may be used as a reference mark 307 for determining (e.g., by the methods described above) the orientation and position of the system 300 and the strut assembly 310. Furthermore, the unique mark 307 may be used as a reference in determining the position and/or orientation by the aforementioned method.

As shown in fig. 60-71 and 75-78, the markings 307 may be spherical knobs or heads of the shoulder screws 302 that removably secure the coupling base plate 303 to the respective platforms 320,330, with a pair of adjacent strut assemblies 310 movably coupled to the coupling base plate 303. Thus, the marker 307 may be positioned outside of the construct 315 and clearly visible in outline. In addition, the markings 307 may be manually engaged to manually thread the shoulder screws 302 into their

respective platforms

320, 330.

As shown in fig. 60-64, the markings 307 may also be used initially to disassemble or prepare the system 300 by removing the shoulder screws 302 to separate the construct 315 from the end plate 371 and the connecting rod 373 extending between the construct 315 and the end plate 371. Each endplate 371 may be coupled to three substrates 303 at one end of the construct 315, with each substrate 303 coupled to a pair of strut assemblies 310. As shown in fig. 60-64, the shoulder screws 302 may each be threadably coupled through a corresponding slot or hole in the end plate 371 and into a corresponding base plate 303 to sandwich the end plate 371 between the collar or shoulder 377 and/or the indicia 307 of the shoulder screws 302 and the corresponding base plate 303. The linkage 373 may be threadably coupled to the base plates 371 and extend between the base plates 371. The end plates 371 and the tie rods 373 may thereby secure the base plate 303, thereby securing the strut assembly 310 together, thereby preventing the strut assembly 310 from extending and retracting.

As shown in fig. 66-81, opposite ends of a pair of adjacent strut assemblies 310 may be movably coupled to substantially opposite lateral sides of a respective base plate 303. As shown in fig. 66-81, each strut assembly 310 may be rotatably coupled to one side of a respective base plate 303 such that the strut assembly 310 is rotatable about at least two axes. The substrate 303 may be triangular and have a curved outer side surface. As shown in fig. 66-81, the base plate 303 may include an outer longitudinal bonding surface 391 and an inner longitudinal bonding surface 393. As shown in fig. 67-76, the outer and/or inner longitudinal engagement surfaces 391,393 may be planar and/or adapted to mate with corresponding surfaces of the studs 50 projecting radially from the

platforms

320, 330. As shown in fig. 67-76, the stud 50 may also have an inner surface and an outer surface corresponding to the engagement surface 391,393 of the base plate 303, such that the base plate 303 may be coupled to and abut the respective inner or outer surface of the stud 50. Further, as shown in fig. 67, 68, and 76, the base 303 may be positioned between and coupled to a pair of platforms 320,330 such that the inner and outer engagement surfaces 391,393 of the base 303 each engage a respective portion of the studs 50 of the pair of

platforms

320, 330.

As also shown in fig. 66-81, the substrate 303 may further include a protrusion 395 extending from the inner bonding surface 391 and/or the outer bonding surface 393. The projections 395 can be located on a laterally and/or radially outward portion of the engagement surface 391,393. As shown in fig. 67-76, the projections 395 may be adapted to fit within corresponding holes, slots, recesses, etc. in the studs 50 of the

platforms

320, 330. The slots of the platforms 320,330 may be open at the outer lateral and/or radial ends of the stud 350 to allow the projections 395 to translate or slide within the openings. As shown in fig. 66-81, in addition to the slots corresponding to the projections 395 of the base 303, the studs 350 of the platforms 320,330 may include holes or portions extending from the slots (or separate from the slots) for enabling the shoulder screws 302 to threadably engage and extend through the holes or portions. The base plate 303 may also include holes for threaded engagement with the shoulder screws 302. In this manner, as shown in fig. 67-76, the projections 395 may be positioned within the respective slots of the stud 350, the engagement surface 391,393 of the respective base plate 303 may engage or abut the respective surface of the stud 350, and the shoulder screws 302 may be threadably engaged and extend into the stud 350 and the base plate 303 to rigidly detachably couple the base plate 303 (and the strut assembly 310 coupled with the base plate 303) and the

respective platforms

320, 330. In some embodiments, as shown in fig. 67-76, the holes or slots of the studs 350 of the platforms 320,330 (which allow the shoulder screws 302 to pass therethrough) may include a chamfer or countersink extending around the hole or slot into the inner and/or outer engagement surfaces 391,393 for receiving therein a corresponding collar or shoulder 377 of the shoulder screws 302. The counter bore and corresponding collar 377 may be used to fixedly or rigidly couple the base plate 303 (and the strut assembly 310 coupled with the base plate 303) and the

corresponding platforms

320, 330.

As shown in fig. 82-92, the system 300 also differs from the

systems

100 and 200 in the construction of a length adjustment mechanism of the strut assembly 310 for selectively changing the arrangement of the strut barrel 305 and the first or second threaded

rod

312, 313. As shown in fig. 82-92, the strut cylinder 305 includes a head at its free end that includes external threads 313 and a cavity 309. The head of the strut cylinder 305 also includes a plurality of holes extending from the external threads 313 to the cavity 309. In some embodiments, at least three apertures may be provided, which may extend radially and be evenly circumferentially spaced. As also shown in fig. 82-92, a ball bearing or other member may be at least partially carried, received, or otherwise positioned within the bore of the head of the strut cylinder 305. In this way, the ball bearings or other components may move at least partially to varying degrees into the cavity 309 or at least partially out of the cavity 309.

As shown in fig. 88, 89 and 92, the length adjustment mechanism of the strut assembly 310 can further include an adjustment nut 306 having a bore, the adjustment nut 306 including a threaded portion 387 and a non-threaded portion 387'. As shown in fig. 92, the adjustment nut 306 and the cavity 309 may be used such that the adjustment nut 306 may be positioned or housed within the cavity 309 using additional space or a portion of the cavity 309. In other words, as shown in fig. 92, the cavity 309 may be larger than the adjustment nut 306 such that the adjustment nut 306 is able to translate within the cavity 309. The length adjustment mechanism of the strut assembly 310 may further include a release nut 398 that is threadably engaged with the external threads 313 of the head of the strut barrel 305. As shown in fig. 89 and 92, the release nut 398 may include an internally threaded surface having a groove or recess therein.

As shown in fig. 92, the groove and threaded portion of the inner surface of the release nut 398 may thereby move the ball bearing or other member into the cavity 309 of the head of the strut cylinder 305 or out of the cavity 309. In this manner, the release nut 398 may be adjusted to push the ball bearing or other component at least partially into the cavity 309 through the threaded portion as shown in FIG. 92, or to a position such that the internal groove is aligned with the ball bearing or other component to allow the ball bearing or other component to move away from the cavity 309 and at least partially out of the cavity 309. Thus, a ball bearing or other member may bias the adjustment nut 306 positioned within the cavity 309 to a position concentric with the threaded rods 312,313 extending through the strut cylinder 305, or allow the adjustment nut 306 to move to a position eccentric to the threaded

rods

312, 313. In the case where the adjustment nut 306 and the threaded rods 312,313 are concentrically arranged, the threaded portion 387 of the adjustment nut 306 may be engaged with the threads of the threaded rods 312,313, and at the eccentric position of the adjustment nut 306, the threaded portion 387 of the adjustment nut 306 may be disengaged from the threads of the threaded rods 312,313, and the non-threaded portion 387' may be engaged with the threads of the threaded rod 312,333. It should be noted that when the position of release nut 398 allows adjustment nut 306 to move within lateral cavity 309, the force between the threads of threaded portion 387 and threaded rods 312,313 may be used to move release nut 398 to the over-center position. In this state, the unthreaded portion 387' may be threadably engaged with the threaded rods 312,313 (assuming that any portion of the adjustment nut 306 is engaged with the threaded rods 312, 313) so that the threaded rods 312,313 are free to translate axially or longitudinally through the strut barrel 305.

As shown in fig. 82-92, the length adjustment mechanism of the strut assembly 310 may further include an adjustment knob 307 having a lower neck region, which adjustment knob 307 may be positioned within the cavity 309 above the adjustment nut 306. As shown in fig. 88-92, the lower neck region of the adjustment knob 307 and the upper portion of the cavity 309 may include a groove, race, or channel between which a plurality of ball bearings or any other rotatable member may be received. The adjustment knob 307 may also include a threaded longitudinally extending bore 391, the bore 391 extending to a top or upper edge of the head of the strut barrel 305. As shown in fig. 88-92, the top or upper edge of the head of the strut barrel 305 may include circumferentially spaced notches, and a spring plunger 399 or other member may be threadably engaged within the bore 391 such that the plunger 399 engages the notches when aligned with the bore 391. Thus, the plunger 399 and the notch may provide a tactile indication of the rotational position of the adjustment knob 307 relative to the strut barrel 305.

As shown in fig. 90, the lower end or portion of the adjustment knob 307 may also include at least one slot 331 (or protrusion) that extends at least partially through the cavity 309. Similarly, as shown in fig. 90, the upper end or portion of the adjustment nut 306 may include at least one protrusion 333 (or slot) extending at least partially through the cavity 309, the protrusion 333 for mating with the slot 331 of the adjustment knob 307. The slot 331 of the adjustment knob 307 and the projection 333 of the adjustment nut 306 may thereby mate such that rotation of the adjustment knob 307 effects rotation of the adjustment nut 306. In this way, the user can rotate the adjustment knob 307 to rotate the adjustment nut 306 within the cavity 309 of the head of the stanchion barrel 305. As described above, the user may also rotate the release nut 398 to adjust its longitudinal or axial position to translate the ball bearing relative to the cavity 309 such that the nut 398 is concentric with the threaded rod 312 or the threaded rod 313 to engage the threaded portion 287. In such an arrangement, the adjustment knob 307 may be rotated to rotate the nut 398 and cause the threaded rod 312 or the threaded rod 313 to lengthen or shorten (whether lengthening or shortening, depending on the direction of rotation) the strut assembly 310 through the strut barrel 305. Thus, the adjustment knob 307 may be used for fine adjustment of the length of the strut assembly 310. To roughly adjust the length of the strut assembly 310, the user may rotate the release nut 398 to adjust its longitudinal or axial position to align the groove with the ball bearing to enable the ball bearing to move away from the cavity 309, thereby enabling the adjustment nut 306 to move eccentrically with the threaded

rod

312 or 313. As described above, at the eccentric position of the adjustment nut 306, the threaded portion is disengaged from the threaded rod 312/313 such that the threaded rods 312,313 are free to translate axially or longitudinally through the strut barrel 305.

Fig. 82-105 illustrate an additional 6DOF bone or tissue external fixation system and associated fixation method 400, the system and method 400 having the desired stability and mobility characteristics of a hexapod system without time consuming strut length selection and assembly difficulties. The external bone or tissue fixation system and associated fixation method 400 shown in fig. 82-105 is similar to the external fixation system and associated fixation method 100 shown in fig. 1-19, the external fixation system and associated fixation method 200 shown in fig. 20-59, and the external fixation system and associated fixation method 300 shown in fig. 20-59. Accordingly, like reference numerals preceded by the numeral "4" are used to indicate like aspects or functions, and the description above with respect to the system and method 100, the system and method 200, and the system and method 300 aspects or functions (and alternative embodiments thereof) is equally applicable to the external fixation system and method 400.

As shown in fig. 82-105, exemplary system 400 differs from

systems

100, 200, and 300 by a rotatable coupling or connection mechanism between strut assemblies 410 (e.g., pairs of oppositely oriented or extended strut assemblies) and platforms or rings 420, 430. As shown in fig. 82-85, the system 400 utilizes a strut mount 441 that is securely and removably coupled and clamped to a corresponding projection 443 of the platforms 420,430 as shown in fig. 84 and 86-89. The mounting member 441 may be used to couple to the platforms 420,430 by clamping the threaded post portion 402 onto the projection 443, with the threaded post portion 402 threadably engaged within a threaded bore 447 positioned adjacent the projection 443. In some embodiments, only the holes 447 of the platforms 420,430 located near or immediately behind the projections 443 may be threaded (i.e., other similar holes of the platforms 420,430 may be non-threaded).

As shown in fig. 84 and 85, threaded post 402 may extend through threaded hole 447 of platforms 420,430 such that a portion of post 402 extends outwardly beyond platforms 420,430 on a side opposite mounting member 441. In some embodiments, this extended portion of the threaded post 402 may be used to couple other mechanisms to the platforms 420, 430. The threaded post 402 may be manually threadably engaged to the threaded aperture 447 of the platforms 420,430 by a fiducial mark 407, the fiducial mark 407 being located at one end of the post portion 402 or extending from one end of the post portion 402. For example, the fiducial marker 407 may be manually engaged by a surgeon or other user, and may be used to rotate the threaded post 402 such that the threaded post 402 is threadably engaged and tightened into the threaded hole 447. Similarly, the fiducial mark 407 may be used to unscrew the threaded post 402 from the threaded hole 447. In some embodiments, the fiducial marker 407 may include a hole or notch for enabling rotation of the threaded post 402 relative to the threaded hole 447 by applying a torque to the fiducial marker 407.

As shown in FIG. 82, mounting member 441 may be used to position fiducial marker 407 inside platforms 420,430 such that threaded post 402 extends from the inside to the outside through threaded hole 447 at least generally along the longitudinal axis of strut assembly 410. In this manner, the fiducial marker 407 may be spaced from the end of the strut assembly 410 and not interfere with the extended nature of the threaded stem portion 412,431 of the strut assembly 410 protruding from the strut barrel 405. Thus, the exterior of the platforms 420,430 (particularly the exterior adjacent the projections 443) may be open and free of any structure that may interfere with the extension of the threaded shank portions 412,413 of the strut assembly 410 from the strut barrel 405 beyond the platforms 420, 430.

As shown in fig. 86-89, each of the platforms 420,430 may include at least three projections 443 extending radially outward from the platforms 420,430 (to couple to a pair of strut assemblies 410, e.g., three pairs of strut assemblies 410 in a hexapod configuration). As shown in fig. 86-89, each projection 443 may include a substantially flat or planar outermost surface in the radial direction. As also shown in fig. 86-89, each projection 443 can include an angled support surface 449, which support surface 449 extends from the planar outer surface and the inner and outer surfaces 451 of the platforms 420, 430. The planar outer surface of the projections 443 may thus be thinner than the main portion of the platforms 420,430 measured between the inner surface 451 and the outer surface 451. The planar outer surface of the projections 443 may be oriented substantially perpendicular to the inner and outer surfaces 451 of the platforms 420, 430. The angled support surface 449 of the projection 443 may thus face the support surface 449 or be angled radially outward and outward or inward from the support surface 449 (e.g., the support surface 449 extending between the outer surface of the projection 443 and the outer surface 451 of the platforms 420,430 may face radially outward and upward and the support surface 449 extending between the outer surface of the projection 443 and the inner surface 451 of the platforms 420,430 may face radially outward and inward). Because mounting members 441 may be positioned on inward-facing surfaces 451 of platforms 420,430, as shown in FIG. 82, mounting members 441 may engage inward-facing support surfaces 449 of projections 443 and inward-facing surfaces 451 of platforms 420,430 to securely clamp to platforms 420,430 as described further below.

As shown in FIGS. 90-83, mounting member 441 may be clamped or coupled to platforms 420,430 (e.g., via projections 443 and threaded holes 447) such that a rear portion of mounting member 441 extends radially outward beyond the outer surfaces of projections 443 and the outer surfaces of platforms 420, 430. As shown in fig. 90-98, the rear portion of mounting member 441 can include a pair of trunnions 453, which trunnions 453 are rotatably coupled within the bore or channel of mounting member 441. As shown in fig. 82-85, trunnions 453 can extend outwardly from respective mounts 441 such that one end or strut barrel 405 of first threaded rod 412 is rotatably coupled to trunnions 453. For example, first threaded rod 412 and strut barrel 405 may be rotatably coupled (e.g., by a pin) to exposed portions of a pair of trunnions 453 of mount 441. The coupling between trunnions 453 and the pair of strut assemblies 410 of each mount 441 may be used to enable relative rotation of strut assemblies 110 about orthogonal axes.

Trunnions 453 can also themselves be used to enable relative rotation of strut assembly 110 about orthogonal axes. For example, trunnions 453 can be rotatable within a bore or channel of mount 441. In some embodiments, mount 441 may be used to enable a limited amount of rotation (e.g., about 300 degrees or 270 degrees) of trunnion 453 relative to mount 441. In some embodiments, as shown in fig. 90-98, 101, and 105, the trunnions 453 can be cylindrical members contained within cylindrical bores or holes of the mount 441. As shown in fig. 97 and 98, the portion of trunnion 453 positioned within mounting member 441 can include a groove that partially encircles or extends around the outer surface of trunnion 453. As shown in fig. 90, 91, 93, 94, and 96-98, the mount 441 can include a trunnion pin or other mechanism (e.g., a spring pin) that extends through a corresponding hole such that the pin fits within a recess of the trunnion 453 (see fig. 97 and 98). The trunnion pin may thereby prevent the trunnion 453 from disengaging from the mount 441 and allow limited rotation of the trunnion 453 within the mount 441. In some other embodiments, a groove may surround trunnion 453 such that trunnion 453 is able to rotate completely or fully within the groove. To allow trunnions 453 to rotate freely and smoothly within mount 441, mount 441 may include an O-ring, washer, or other similar member 457 located between a pair of trunnions 453, as shown in fig. 98.

As shown in fig. 90, 93-103, the threaded post 402 may be movably retained or received within the locking bore 477 of the mounting member 441 by a stud or other member 457, such as a spring stud. As shown in fig. 93, 97, 98, and 103, the mounting member 441 can include a keyhole or other irregularly shaped aperture 477 extending through between the outer surface and the engagement surface 467. As shown in fig. 93, engagement surface 467 of mount 441 can engage the inner surfaces of platforms 420,430 during use. As shown in fig. 93 and 97, the post 402 may include a threaded portion 465, a conical or beveled ledge 459, and a non-threaded portion 463 extending between the threaded portion 465 and the beveled ledge 459. The non-threaded portion 463 of the post 402 may define a smaller diameter or width than the threaded portion 465 and the angled ledge 459. As shown in fig. 98, irregularly shaped bore 477 may include a first portion sized to allow threaded portion 465 to pass therethrough and a second portion sized to prevent threaded portion 465 from passing through irregularly shaped bore 477, but to allow non-threaded portion 463 to pass through or seat in bore 477 from irregularly shaped bore 477. To position post 402 within irregularly shaped bore 477 and movably couple post 402 to mount 441, stud 457 may pass at least partially through a first portion of irregularly shaped bore 477, wherein non-threaded portion 463 positioned on stud 457 may at least partially block the first portion. Because the second portion of the irregularly shaped bore 477 is too small for the threaded portion 465 and the angled flange 459 to pass through, the post 402 may be effectively received within the irregularly shaped bore 477. Thus, mount 441 may include an aperture or channel for positioning stud 457 at least partially through a first portion of irregularly shaped aperture 477. In use, the mounting 443 may be pre-assembled with the post 402 received within the mounting 443 by the pintle 457.

As shown in fig. 93, 97, 99, 102, and 103, the outer surface of the mounting member 441 opposite the engagement surface 467 can include a chamfer or countersink surrounding the portion of the irregularly shaped bore 477 corresponding to the tapered or beveled flange 459. The countersink of the irregularly shaped bore 477 can be positioned at least partially within or about the second smaller portion of the irregularly shaped bore 477. In this manner, as shown in fig. 90, 92-95, 97 and 98, when the threaded portion 465 of the post 402 is torqued down into the threaded hole 447 of the landings 420,430, the engagement surface 467 abuts and engages the inner surface 451 of the landings 420,430 and the angled flange 459 is self-supporting or self-centering into the countersunk portion of the irregularly shaped bore 477.

As shown in fig. 84, 93, and 97, the counter bore of the irregularly shaped bore 477 may also be used to pull or translate the mounting member 441 radially inward such that the lip or arm 445 of the mounting member 441 engages the inner angled support surface 449 of the projection 443 of the platforms 420, 430. As shown in fig. 84, 93, 94, 95, 97, 99, 101, and 105, the lip or arm 445 of the mounting member 443 may extend axially inward from the engagement surface 467 and radially inward toward the interior or center of the platforms 420, 430. Thus, as shown in fig. 84 and 93, the lip 445 of the fitting 443 can extend along or around the planar outer surface of the projection 443 and the inwardly angled support surface 449. Further, the mounting member 441 and the projection 443 can be used such that when the threaded portion 465 of the post 402 is twisted down into the threaded aperture 447 of the landings 420,430, the engagement surface 467 abuts and engages the inner surface 451 of the landings 420,430 and the angled flange 459 seats itself in the countersunk portion of the irregularly shaped aperture 477 translating the mounting member 441 radially inward with the lip 445 engaging the inner angled bearing surface 449 of the projection 443. In this manner, mount 441 may be clamped to inner surface 451 of platforms 420,430 and inner angled support surface 449 to securely couple to platforms 420, 430. It should be noted that when the mount 441 is clamped to the platforms 420,430, the remainder of the lip 445 may be spaced slightly from the outer planar surface of the projection 443 and the outer angled support surface 449, as shown in fig. 93.

In use, the threaded portion 465 of the post 402 may be threaded into the threaded hole 447 associated with one of the projections 443 of one of the platforms 420, 430. The non-threaded portion 463 of the post 402 may be positioned within the second, larger portion of the irregularly shaped bore 477, allowing the lip 445 to extend beyond the outer surface and tilt the support surface 449 of the projection 443. As the post is torqued and tightened into threaded bore 447, ramped flange portion 459 can engage the counterbore of irregular shaped bore 477 and seat itself on mounting member 441 by translating mounting member 441 radially inward (and non-threaded portion 463 translates toward or partially into the first smaller portion of irregular shaped bore 477). Thus, engagement surface 467 of mounting member 441 can be caused to abut and abut inward supporting or engagement surface 451 of platforms 420, 430. This radially inward movement or translation of the mounting member 441 may thus cause the lip 445 of the mounting member 441 to engage or abut the inner angled support surface 449 of the projection 443. In this manner, mount 441 (and thus the strut assembly coupled to mount 441) may be clamped onto angled support surface 449 of projection 443, inward support or engagement surface 451 of platforms 420,430, and threaded hole 447 of platforms 420, 430.

It is to be understood that the above description is intended to be illustrative, and not restrictive. Many alterations and modifications may be made by those having ordinary skill in the art based on the teachings herein without departing from the general spirit and scope of the invention as defined by the appended claims and their equivalents. For example, the above-described embodiments (and/or aspects thereof) may be used in combination with each other. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the various embodiments without departing from the scope thereof. While the dimensions and types of materials described herein are intended to define the parameters of the various embodiments, they are by no means limiting and are exemplary only. Many other embodiments will be apparent to those of skill in the art upon reading the above description. The scope of various embodiments should, therefore, be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled. In the appended claims, the terms "including" and "in which" are used as the equivalents of the respective terms "comprising" and "wherein". Furthermore, in the appended claims, the terms "first," "second," and "third," etc. are used merely as labels, and are not intended to impose numerical requirements on their objects. Further, the term "operably coupled" is used herein to refer to both couplings resulting from separate distinct components being directly or indirectly coupled and from integrally formed components (i.e., a single piece). Furthermore, the appended claims are not written in a device-plus-function format and are not intended to be interpreted based on 35u.s.c § 112, sixth paragraph, unless the claims expressly use the phrase "means for … after the functional description without other structure. It is to be understood that not necessarily all such objects or advantages described above may be achieved in accordance with any particular embodiment. Thus, for example, those skilled in the art will recognize that the systems and techniques described herein may be embodied or carried out in a manner that achieves or optimizes one advantage or group of advantages as taught herein without necessarily achieving other objects or advantages as may be taught or suggested herein.

While the invention has been described in detail in connection with only a limited number of embodiments, it should be readily understood that the invention is not limited to such disclosed embodiments. Rather, the invention can be modified in conjunction with any number of variations, alterations, substitutions or equivalent arrangements not heretofore described, but which are commensurate with the spirit and scope of the invention. Additionally, while various embodiments of the invention have been described, it is to be understood that aspects of the invention may include only some of the described embodiments. Accordingly, the invention is not to be seen as limited by the foregoing description, but is only limited by the scope of the appended claims.

This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to practice the invention, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be included within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal languages of the claims.

Claims

1. A strut assembly for an extraosseous fixation system and which is length adjustable, the strut assembly comprising:

an internally threaded strut assembly comprising a first articulating end for rotatably connecting with a first external fixation platform for connecting with a first bone segment;

an externally threaded rod assembly translatably threaded within the internally threaded strut assembly to selectively adjust the axial length of the adjustable length strut assembly, the externally threaded rod assembly comprising:

a base externally threaded rod member including a first internally threaded opening extending from a first end, and a joint at a second end; the joint is configured to rotatably couple with a second external fixation platform configured to connect to a second bone segment; the first internally threaded opening defines a first pitch;

an additional externally threaded rod member including a second internally threaded opening extending from a third end thereof, the second internally threaded opening defining a second thread pitch that is less than the first thread pitch; and

a connecting element including a first external thread portion having the first thread pitch, a second external thread portion having the second thread pitch, and a non-threaded portion positioned axially between the first external thread portion and the second external thread portion;

wherein the first externally threaded portion of the connecting element is for threadingly engaging and axially translating within the first internally threaded opening of the base externally threaded rod member; the second externally threaded portion of the connecting element being adapted to threadingly engage and axially translate within the second internally threaded opening of the additional externally threaded rod member, an

Wherein rotation and axial translation of the first externally threaded portion of the connecting element within the first internally threaded opening and the second externally threaded portion of the connecting element within the second internally threaded opening causes the base externally threaded rod member and the additional externally threaded rod member to be drawn axially together until the end faces of the first end and the third end abut.

2. The strut assembly according to claim 1, wherein the first externally threaded portion of the connecting element is located within the second internally threaded opening of the additional externally threaded rod member such that at least a portion of the second externally threaded portion of the connecting element is positioned beyond the third end.

3. The strut assembly according to claim 2, wherein said externally threaded rod assembly is provided such that: initial rotation of the connecting element rotates the connecting element and the additional externally threaded rod member relative to the base externally threaded rod member such that the second externally threaded portion of the connecting element advances into the first internally threaded opening.

4. The strut assembly according to claim 2, wherein said first and third ends each include at least one keyed element extending axially toward one another, said keyed elements including an engagement face, the engagement faces of said first and third ends being arranged to: the base externally threaded rod member and the additional externally threaded rod member engage each other when they are axially drawn together by the connecting element.

5. The strut assembly according to claim 4, wherein the interface of the first and third ends is provided as: when the connecting element is rotated and advanced into the first internally threaded opening, the base externally threaded rod member and the additional externally threaded rod member are prevented from relative rotation and allowed to translate axially therebetween.

6. The strut assembly according to claim 5, wherein said key includes a protrusion extending axially beyond end faces of said first and third ends, and wherein said first and third ends include: a recess for receiving a key associated with the other end when the first end and the third end are in abutment.

7. The strut assembly according to claim 1, wherein the external threads of said base externally threaded rod member and said additional externally threaded rod member together form a uniform and synchronized pitch when said first and third ends are in abutment.

8. The strut assembly according to claim 1, wherein said additional externally threaded rod member further comprises a third internal opening extending from a fourth end thereof, said fourth end being opposite said second end, said third internal opening being in communication with said second internally threaded opening such that said connecting element is accessed from said fourth end.

9. The strut assembly according to claim 8, wherein said third inner opening comprises an internal thread having said first pitch extending from said fourth end.

10. The strut assembly according to claim 8, wherein an axial end of the second externally threaded portion includes a drive detail for providing torque transmission to the connecting element.

11. The strut assembly according to claim 1, wherein rotation and axial translation of the first externally threaded portion of the connection element within the first internally threaded opening and the second externally threaded portion of the connection element within the second internally threaded opening causes the length of the connection element being advanced into the first internally threaded opening to be greater than the length of the connection element being advanced into the second externally threaded portion.

12. The strut assembly according to claim 1, wherein said externally threaded rod assembly is provided as: the non-threaded portion of the connecting element extends within the first and second internally threaded openings when the end faces of the first and third ends are in abutment.

13. The strut assembly according to claim 1, wherein the adjustable length strut assembly comprises at least six adjustable length strut assemblies.

14. The strut assembly according to claim 13, wherein the at least six adjustable length strut assemblies are coupled to one another and form a unitary construction prior to being coupled to the first and second platforms.

15. The strut assembly according to claim 13, wherein the at least six adjustable length strut assemblies are connected to the first and second platforms in pairs of strut assemblies spaced around the first and second platforms, and wherein each pair of strut assemblies comprises a first strut assembly connected to the respective platform by a joint of an externally threaded base rod member and a second strut assembly connected to the respective platform by a first joint end of an internally threaded strut assembly.

16. The strut assembly according to claim 1, wherein the internally threaded strut assembly comprises a nut, and wherein the axial length of at least one strut assembly of adjustable length is adjusted by selective rotation of the nut in engagement with the external threads of the externally threaded rod assembly.

17. The strut assembly according to claim 16, wherein said nut is selectively threadably translatable along the external threads of said base externally threaded rod member and said additional externally threaded rod member.

18. The strut assembly according to claim 16, wherein said nut is partially threaded, and wherein the threaded portion of said nut is biased into engagement with the external thread of at least one strut assembly of adjustable length by a release nut engaging the external thread of said internally threaded strut assembly.

19. The strut assembly according to claim 18, wherein translation of said release nut along said internally threaded strut body assembly in a first axial direction forces said nut into threaded engagement with the external threads of said internally threaded strut body assembly, and translation of said release nut along the internally threaded strut body assembly in a second axial direction allows said release nut to be threadedly disengaged from the external threads of said internally threaded strut body assembly.

20. The strut assembly according to claim 1, wherein the strut body portion comprises a first joint at an end thereof for coupling to a first fixed platform and the first externally threaded shank portion comprises a second joint at a second end thereof for connecting to a second fixed platform.